Cornell Dubilier Responds to the Needs of Next-Gen Level 3 EV Charger Designers

In response to the rapidly growing demand for higher-performance DC link
capacitors for EV chargers, Cornell Dubilier Electronics (CDE) has expanded
its standard-product offerings and brought to light its advanced custom
capacitor capabilities. While the inverter circuitry at the heart of EV
charging stations may seem familiar to design engineers, there are
operational, environmental, and mechanical demands that make Level 3 EV
charging stations unique. The latest designs are pushing voltages and
current handling to higher levels to shorten recharge times.

According to Bob Kropiewnicki, Director of Applications Engineering of CDE,
“We’ve found that design engineers engaged in Level 3 charger projects are
faced with a balancing act to mitigate significant circuit harmonics that
cause heating problems. Adequate input and output filtering, strategic
current paths, and reducing inductance and ESR are all concerns.”
Kropiewnicki continued, “All too often, the DC link capacitor is an
afterthought which forces those problems to be dealt with in ways that are
more complex than necessary. A better solution is to focus on the
requirements of the DC link as early as possible in the design process. We
are able to predict performance by using our advanced capacitor modeling
based on project application conditions.”

Before the EV charger market started to take off, CDE was already deeply
involved in the design and manufacture of DC link and pulse power capacitors
for high-power applications in military and green-energy fields. This base
was further enhanced by the acquisition of the custom film capacitor
division of NWL in 2021.

Components available include screw terminal and snap-in aluminum
electrolytics as well as polypropylene film capacitors; air or water-cooled
types, with oil-impregnated or dry-epoxy construction. Constructions include
multiple terminal options in metal or plastic cases. CDE’s process begins
with the customer providing the required specifications, including life and
other application requirements. These specifications help determine if a
standard or custom solution is recommended. To validate the recommendation,
CDE utilizes advanced in-house thermal modeling and product testing
capabilities. CDE has dedicated engineering resources to design custom DC
link capacitors that meet the exact power requirements and unique mechanical
packaging to fit complex applications. On the manufacturing side, the
company has multiple North American manufacturing facilities.

CDE’s custom-engineered DC Link capacitors are designed specifically for
Level 3 EV charging applications. The high-power demands of Level 3 charging
require robust DC link capacitors, having exceptional life and reliability
over a broad range of operating conditions. CDE offers high capacitance
values with low inductance (< 5 nH), high ripple current (100s of Amps),
self-healing, and low loss dielectrics. Voltage Range: 450 Vdc to 3800 Vdc.
-40 °C to +135 °C Operating Temperature, with life expectancies of 200,000
hours typical.

For additional information, visit CDE’s website:
https://www.cde.com/new-product/ev-charging/

Cornell Dubilier (Cornell Dubilier Electronics, Inc., Cornell Dubilier
Marketing, Inc., and affiliates) is dedicated to advancing capacitor
technology for new applications. Cornell Dubilier combines innovative
products with engineering expertise to provide reliable component solutions
for inverters, wind and solar power, electric vehicles, power supplies,
motor drives, HVDC, motors, welding, aerospace, telecom, medical equipment,
and UPS systems. A global group of companies, Cornell Dubilier has ISO-9001
certified manufacturing and distribution facilities in Liberty, SC; New
Bedford, MA; Snow Hill, NC, Mexicali, Mexico; and Hong Kong.